Water heater



R. l. PABODIE.

WATER HEATER.

APPLICATION FILED FEB. 18, 1920.

Patented Oct. 3, 1922.

INVENTOR 4 (amt. O ,1 A {M ATTORNEYS Patented Unit. 3,, 122..

ROBERT JEWETT PABODIE, 0F MAYWOOD, ILLINOIS, ASSIGNOR TO THE GRISCOIVIRUSSELL COMPANY, OF NEW'YORK, N. Y., A CORPORATION OF DELAWARE.

WATER HEATER.

Application filed February 18, 1920. Serial No. 359,570.

To all whom it may concern:

Be it known that I, Ronnn'r J. PABODIE, a citizen of the United States,residing at Maywood, in the county of Cook, State of Illinois, haveinvented certain new and useful Improvements in Water Heaters; and I dohereby declare the following to be a full, clear, and exact descriptionof the invention, such as will enable others skilled in the art to whichit appertains to make and use the same.

This invention relates to heaters for water or other liquids of the kindcommonly known as storage heaters, that is, a heater which maintainswithin itself a considerable quantity of water at the desiredtemperature with heating means to replace the heat units lost byradiation and to heat the incoming cold water Which replaces the hotwater drawn oil from time to time. Heaters-of this kind are used wherethe requirements for hot water are not constant, the large storagecapacity permitting the temperature to be built up gradually whilepermitting a large quantity to be used at one time. Such heaters as nowconstructed are not as ellicient as so-called instantaneous heaterswhich are generally employed where the use of hot water is more or lessuniform, due largely to the fact that in storage heaters as nowconstrue-ted the velocity of the water through the heating path is lowand the rate of heat absorption correspondingly small. I

The object of the present invention is to provide a heater of thestorage type which is as efficient in its action as an instantaneousheater, that is, one in which the heat transferred per unit of surfacewill be as large or larger thanin the ordinary instantaneous heater andin which the other advantages of a high velocity fiow, such as scouringeffect, freedom from scaling, etc., will be obtained.

A further object of the invention is to provide a heater of this classin which the size of the apparatus necessary for the given demand andfluctuation in output is reduced, due to the more rapid and eliicientoperation of the heater, whereby the incoming water will be to a largeextent heated during its flow into the reservoir.

A further object of the invention is to provide a device of simple andcheap construction in which the heating surface may be readily withdrawnfor cleaning or repair.

In the accompanying drawings I have illustrated two dilferentembodiments of my invention, and in the said drawings,

Figure 1 is a longitudinal section through one form of my improvedheater;

Fig. 2 is a transverse section on line 2-2 of Fig. 1;

Fig. 3 is a longitudinal section of the second form of heater; and

-Fig. 1 is a transverse section through the auxiliary heating elementshown in Fig. 3.

Referring to the drawings, particularly to Figs, 1 and 2, 1 indicatesthe shell or container for the water to be heated and stored. thecapacity of the shell depending upon the quantity ofwater which it isdesired to maintain on hand, which in turn depends upon fluctuations indemand to be met and also upon the rapidity with which the heatingelements can restore to the replenishing water the necessary heat torestore the entire contents of the shell to the desired temperature.

As shown, the shell is of the ordinary cylindrical horizontal type withan outlet 2 for the heated water at the top and a drain or blowdownoutlet 3 at the bottom for the removal of sediment. The water in theshell is heated by the heating element comprising, as shown, acylindrical or tubular .shell 5 of thin metal supported in the container1 in" the manner shown with a series of tubes for the passage of thewater to be heated, the tube surface being so proportioned that theheating element is in effect an instantaneous heater and delivers thewater to the storage shell at approximately the temperature which it isdesired to maintain.

As shown, the tubes themselves are grouped to provide a triple pass forthe water through the shell. All the tubes are supported at theoutboardend of the shell in a header or tube plate 7 attached to theshell and clamped to'the flange of the shell by a cover plate 8containing the water inlet port 9 and provided with a partition 10separating the upper group oftubes from the two lower groups. The otherends of the tubes are. supported by a floating head or drum 11 mountedto slide axially in the shell. the head being surrounded by a packedjoint 12 which permits the sliding movement of the head as effected bythe expansion and' contraction of the tubes. The floating head isdivided by a transverse partition into an upper compartment connectingthe two upper groups of. tubes and a lower compartment for the bottomgroup of tubes whereby the incoming water is caused to successivelytraverse the three groups of tubes before it is discharged through theoutlet opening 13 in the cover plate of the floating head. I

The preferred heating. medium for the water in the tubes of the heateris the exhaust steam from the auxiliary engines if the heater is used onshipboard or from any other suitable source, for instance the drivingengine of an industrial plant or the steam heating system of thebuilding, when the heater is used in an oflice building or similarplace. The steam isadmitted to the shell through a steam inlet 15 at thetop of the shell and a drain 16 is provided at the lower s'de of theshell for draining ofl the water of condensation.

WVhen exhaust steam 'is employed as the heating medium and is condensedin the shell 5 the packed joint 12 is particularly efiicacious for thereason. that the pressure in the storage reservoir exceeds that in theshell 5 and the joint is therefore self-packing. l/Vhere the heaterwater is to be used for drinking or other purposes where purity isrequired, this self-packing joint is particularly important as theexhaust steam usually contains oil etc., which would contaminate thewater.

The rear end of the storage shell is provided with the usual man-hole14; giving access to the interior of the reservoir, and the variousinlet and outlet ports will be provided with pipes having the usualvalves, not shown, for controlling the intake and delivery of the water.Also, there is preferably provided an intake valve 17 for the exhauststeam which may, if desired, be

thermostatically controlled by any suitable means, not shown.

The operation of the apparatus will be obvious from the abovedescription. \Vhen there is no Water being drawn from the tank therewill be no flow through the tubes 6, but the shell 5 will furnishsufficient heating surface to supply all the heat necessary to make upfor losses through radiation. When, however, the water is being drawnoff there will be a rapid inflow through the tubes 6, so that the tubesurfaces will act at their maximum efficiency as heat-absorbingsurfaces, delivering the water through the outlet 13 into the tankat atemperature almost,'if -not quite, that-desired for water drawn'ofl fromthe reservoir. Hence, when the outlet is again out off the temperaturewill be quicklybuilt up to the desired maximum.

of water maintained on hand and the constant utilization of the exhauststeam which in the ordinary instantaneous heater is utilized only whilethe water is running. Also, in the instantaneous heater there areconsiderable heat losses fromthe surface of the shell of the tubes whichin my improyed heater serves as a heat transfer surface to the water inthe storage reservoir. Over the usual storage heater my improved heaterhas the advantage, in addition to the greater efficiency, that there canbe no possible short circuit of water from the cold water inlet to theoutletwhen the water is drawn off.

In Figs. 3 and a I have shown a modified apparatus designed to take careof wide fluctuations in the demand for water without unduly increasingthe size of the storage reservoir. To this end, in addition to the mainheater whose shell is indicated at 5, and which occupies the sameposition in the main take 1 as the previously described construction, Iprovide an auxiliary or supplemental heater comprising a smallcylindrical shell 20 positioned in the reservoir near the top thereofand provided with inlet and outlet pipes 21, 22 for the admission anddischarge of the steam from the shell. Contained within the shell arethree tubes 23, 23 and 23, respectively, the tubes being supported attheir outer ends in a tube sheet 24: covered by a cap 25 having a webdividing the chamber formed with the tube sheet into two compartments,one of the compartments connecting with the tube 23 while the othercompartment is connected to tubes 23 and 23. The other end of the tubesare supported in a floating head 26 which is also divided into twocompartments, one compartment connecting tubes 23 and 23 ,while theother connects tube 223 with an inlet port 27 in the cover plate of thefloating head.

The outlet 28 for the water heated by the auxiliary heater is attachedto the chamber of the head 25 which connects with the pipe 23" so thatthe water entering the inlet 27 traverses all three pipes beforereaching the outlet.

It is not intended that the auxiliary heater. or booster, shall be usedat all times, but only when the consumption of water from the tank. istoo rapid for the main heater to maintain the desired temperature, Thesteam inlet to the auxiliary heater will therefore be provided with acut-off valve 30 so that the steam may be turned on and off as desired.

I preferably employ thermostatic control for the valve 30. Thethermostat. which is indicated diagrammatically at 33, has its 1 ,aa evecontrol element projected into the reservoir and operates to shift thevalve rod 32 to open the valve 30 when the temperature of the waterfalls below a desired minimum so as to turn on the steam and add theheating effect of the booster to that'of the main heater. then, however,the demand for water is not excessive, the temperature in the reservoirwill be built up beyond the limit for which the thermostat is set andthe thermostat will act to close the valve 30 and render the auxiliaryheater ineffective.

I have shown both the main heater and the booster as arranged to providea triple pass for the water before its discharge, but it will of coursebe understood that the tubes may be arranged to provide any odd' numberof passes, or in fact an even number of passes may be provided by havingthe inlet and outlet to the tubes at opposite ends of the tubes.

In the foregoing specification I have described the details ofconstruction of my improved heater in the form which I have so far foundmost practical for commercial use. It is to be understood, however, thatthe invention is not limited to the details described and shown but thatit may be varied in many particulars without departing from the scope ofthe invention as set forth in the appended claims.

I claim:

1. In a liquid heater, the combination of a storage reservoir, a heatingelement in said storage reservoir adapted to receive a fluid heatingmedium, said heating element having a heat transferring surface incontact with the liquid in said reservoir, and means for heating theliquid admitted to said reservoir, said means comprising a passagewayfor the liquid in heat exchanging relation with said heating fluid.

2. In an apparatus of the class described, the combination of areservoir for water to be heated, a heater projecting into saidreservoir comprising a heat conducting shell for receiving a fluidheating medium, a se ries of tubes in said shell in heat exchangingrelation with said heating medium, a discharge outlet from said tubes tosaid reservoir and an inlet port for the water to be heated connected tosaid tubes.

3. In an apparatus of the class described, the combination of areservoir for water to be heated, a heater projecting-into saidreservoir comprising a heat conducting shell for receiving the heatingmedium, said shell being in contact with the water in thereservoir, aplurality of tubes in said shell, sa d tubes being connected in series;and a discharge outlet for some of said tubes whereby the waterdelivered to said reservoir will pass more than once through the shellbefore entering the reservoir.

i. In an apparatus of the class described,

the combination of a reservoir for water to be heated, a heaterprojecting into said reservoir comprising aheat conducting shell forreceiving the heating medium, a series of tubes in said shell, adischarge outlet from said tubes to said reservoir and an inlet port forthe water to be heated connected to said tubes, the outer surface ofsaid shell constituting a heating surface for the water in thereservoir.

5. In an apparatus of the class described, the combination of areservoir for water to be heated, a heater therefor comprising a shellof heat conducting material projecting part way into said reservoir nearthe bottom thereof, said shell being in contact with the water in thereservoir, a plurality of tubes within the shell, an inlet chamber atthe outer end of said shell of heat conducting material, a dischargechamber connected to the other end of said shell having a portconnecting with the interior of the reservoir and connections to saidshell without the reservoir for admitting the heating medium to theinterior of the shell to heat the Water passing through the tubes.

6. In an apparatus of the class described, the combination of areservoir for water to be heated, a heater therefor arranged at thebottom of said reservoir, said heater having a, pair of compartmentsseparated by heattransferring surfaces, means for admitting the water tobe heated to one of said compartments, a discharge outlet from saidcompartment into said reservoir, means for admitting a heating medium tothe other compartment, said last mentioned compartment having a. portionof its surface in heat-transferring contact with the water in the reserV011.

7. In a water heater, the combination of a reservoir for the water to beheated, and a heating element comprising a cylindrical shell of heatconducting material projecting into said reservior in substantiallyhorizontal position with one end projecting through the wall of thereservoir, a plurality of tubes in said shell, said tubes and said shellforming, one the chamber for the heating medium and one the chamber forthe water to be heated, the latter chamber having a discharge opening insaid reservoir and connections to said chambers without the reservoirfor the heating medium and the water to be heated, respectively.

8. In a water heater, the combination of a reservoir, a heat conductingshell projecting into the reservoir, a series of tubes in the shell,said tubes being divided into three groups, a head at the outer end ofthe shell divided into two chambers, one of said chambers connecting twoof said groups, a head at the opposite end of said shell and within saidreservoir, said head being also divided into two compartments with onecompartment connected to tWo groups of said tubes, the arrangement beingsuch that the three groups of tubes are connected in series, an inletport for the chamber at the outer end of said shell Which is connectedto the single group of tubes, a discharge port from the compartment atthe inner end of said shell which is connected to the other single groupof tubes, and means for admitting a heating 10 fluid to the shell.

9. In a heater, the combination of a storage reservoir, a heatingelement in said storage reservoir, comprising a chamber for'containingthe heating vapor and a passage for the liquid to be heated in heatexchanging relation therewith, and connections for passing the liquidsupplied to the reservoir through sald passage before admission to thereservoir.

In testimony whereof I afiix my signature.

ROBERT JEWETT PABODIE.

